If you’re making New Year’s resolutions, here’s one for the top of your list: I won’t complain about a surprise tax bill or lower refund if I neglected to check my withholding. The 2017 tax overhaul made major changes to the code, such as limiting the deduction for state and local taxes and greatly expanding the tax credit for children under 17. The Treasury Department required employers and pension payers to lower withholding for 2018.

The IRS recently warned that the number of filers who owe tax or penalties for 2018 is likely to be larger than in recent years, adding that “many of them are likely to be people who have always gotten refunds.”